Officials say an error in an electronic train signaling system caused the derailment and crash that killed 275 people and injured hundreds more in India Friday.
The signal system caused a passenger train to incorrectly change tracks, where it then collided with a freight train, investigators say.
The high-speed Coromandel Express moved from the main track line to a secondary track, and struck a train carrying iron ore. The passenger train's derailed coaches obstructed another track, which caused the Yesvantpur-Howrah Express passenger train to also derail, as it approached from the opposite direction.
Officials did not know yet whether the signal error was a technical problem, or human error. They said none of the trains involved were speeding.
An anonymous state official said Sunday the death toll from the accident was over 300 people. An Odisha government statement later on Sunday said 275 people died in the crash.
India train crash kills over 280, injures 900 in major rail disaster
A railroad ministry spokesperson said one train derailed and then was hit by another train coming from the opposite direction.
Workers were cleaning the crash site on Sunday, using excavators to clear debris and beginning repairs to the tracks.
Late Saturday, 15 more bodies were recovered from the scene.
Also on Saturday India's Prime Minister Narendra Modi visited survivors in the hospital, and promised them government assistance.
Some 22 million people ride trains in India's network every day. Officials want to modernize the country's rail infrastructure, which sees several hundred accidents every year. Officials say most accidents are due to outdated signaling systems, or human error.
